CA2694319A1 - Evaluation of the feedback quality in communications systems - Google Patents
Evaluation of the feedback quality in communications systems Download PDFInfo
- Publication number
- CA2694319A1 CA2694319A1 CA2694319A CA2694319A CA2694319A1 CA 2694319 A1 CA2694319 A1 CA 2694319A1 CA 2694319 A CA2694319 A CA 2694319A CA 2694319 A CA2694319 A CA 2694319A CA 2694319 A1 CA2694319 A1 CA 2694319A1
- Authority
- CA
- Canada
- Prior art keywords
- communications device
- signal
- communications
- transmitted
- measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004891 communication Methods 0.000 title claims abstract description 87
- 238000011156 evaluation Methods 0.000 title description 2
- 230000005540 biological transmission Effects 0.000 claims abstract description 27
- 238000012360 testing method Methods 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 18
- 238000012986 modification Methods 0.000 claims description 13
- 230000004048 modification Effects 0.000 claims description 13
- 230000001419 dependent effect Effects 0.000 claims description 6
- 238000005259 measurement Methods 0.000 claims description 4
- 238000012545 processing Methods 0.000 description 8
- 230000006978 adaptation Effects 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
- 238000012795 verification Methods 0.000 description 3
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/20—Monitoring; Testing of receivers
- H04B17/24—Monitoring; Testing of receivers with feedback of measurements to the transmitter
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/20—Monitoring; Testing of receivers
- H04B17/21—Monitoring; Testing of receivers for calibration; for correcting measurements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/0082—Monitoring; Testing using service channels; using auxiliary channels
- H04B17/0085—Monitoring; Testing using service channels; using auxiliary channels using test signal generators
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/0082—Monitoring; Testing using service channels; using auxiliary channels
- H04B17/0087—Monitoring; Testing using service channels; using auxiliary channels using auxiliary channels or channel simulators
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
- H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
- H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
- H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Mobile Radio Communication Systems (AREA)
- Radio Transmission System (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Abstract
A measuring system for testing a feedback signal quality, transmitted by a communications device within a communications system, is provided. This measuring system includes a measuring device which transmits a signal to the communications device. The signal is received by the communications device and a feedback signal is generated by the communications device indicating the transmission conditions of the signal. The measuring device then measures actual reception quality of the signal in the communications device and compares the measured transmission quality with the feedback signal.
Description
Evaluation of the feedback quality in communications systems The invention relates to a measuring system and a method for determining the quality of the feedback (feedback) of the received-signal quality transmitted by communications devices within communications systems, especially MIMO
communications systems (Multiple-Input Multiple-Output communications systems).
In communications systems, such as UMTS or WiMax, the feedback transmitted by participating devices with reference to the channel quality is conventionally used for the adaptation of the transmission, for example, of the base station. For instance, in a closed-loop method, the pre-coding is modified in order to guarantee optimum reception at the terminal-device end. However, this method relies on as accurate an estimation of the transmission conditions or mobile-radio channel properties as possible at the receiver end. Although the participating devices are equipped with corresponding functions, no methods and devices for the verification of the correct function are so far known.
For example, European Patent Application EP 1 890 413 A2 discloses methods and devices for the transmission and reception of such feedback information from a communications device to a base station. However, a verification of this feedback information is not disclosed.
communications systems (Multiple-Input Multiple-Output communications systems).
In communications systems, such as UMTS or WiMax, the feedback transmitted by participating devices with reference to the channel quality is conventionally used for the adaptation of the transmission, for example, of the base station. For instance, in a closed-loop method, the pre-coding is modified in order to guarantee optimum reception at the terminal-device end. However, this method relies on as accurate an estimation of the transmission conditions or mobile-radio channel properties as possible at the receiver end. Although the participating devices are equipped with corresponding functions, no methods and devices for the verification of the correct function are so far known.
For example, European Patent Application EP 1 890 413 A2 discloses methods and devices for the transmission and reception of such feedback information from a communications device to a base station. However, a verification of this feedback information is not disclosed.
2 The invention is based upon the object of providing a measuring system and a measuring method, which, with a low cost, tests the feedback signals from communications devices.
According to the invention, the object is achieved with reference to the method by the features of the independent claim 1 and with reference to the device by the features of the independent claim 7. Advantageous further developments form the subject matter of the dependent claims referring back to these claims.
A measuring system for testing a feedback signal transmitted by a communications device within a communications system comprises an antenna system and a measuring device. The measuring device transmits a signal to a communications device via the air interface and the antenna system. The communications device receives the signal and generates a feedback signal dependent upon the transmission conditions it has determined and transmits it to the measuring device. The measuring device measures the actual reception quality of the signal in the communications device. In this context, the measuring system implements the following stages:
- the measuring system modifies the signal transmitted to the communications device in such a manner that the transmitted feedback signal displays no further possibility of improvement of the transmission conditions;
- the transmitted signal and/or the position of the communications device and/or of the antenna system is modified by the measuring device;
- the measuring device compares the feedback signal and the actual reception quality and in this manner
According to the invention, the object is achieved with reference to the method by the features of the independent claim 1 and with reference to the device by the features of the independent claim 7. Advantageous further developments form the subject matter of the dependent claims referring back to these claims.
A measuring system for testing a feedback signal transmitted by a communications device within a communications system comprises an antenna system and a measuring device. The measuring device transmits a signal to a communications device via the air interface and the antenna system. The communications device receives the signal and generates a feedback signal dependent upon the transmission conditions it has determined and transmits it to the measuring device. The measuring device measures the actual reception quality of the signal in the communications device. In this context, the measuring system implements the following stages:
- the measuring system modifies the signal transmitted to the communications device in such a manner that the transmitted feedback signal displays no further possibility of improvement of the transmission conditions;
- the transmitted signal and/or the position of the communications device and/or of the antenna system is modified by the measuring device;
- the measuring device compares the feedback signal and the actual reception quality and in this manner
3 determines the quality of the feedback signal.
Accordingly, the testing of the feedback signal is guaranteed. The cost of the measuring system is low.
By preference, the measuring device is connected to the communications device. The measuring device preferably determines the actual reception quality by determining the bit-error rate and/or the data rate. A simple determination of the actual_ transmission quality is therefore achieved.
The antenna system is advarltageously a multiple antenna system. By preference, the communications device receives the signals by means of several antennae. In particular, in communications systems cf high complexity, it is possible to determine the accuracy of the feedback signals at low cost.
The measuring device preferably brings about the modification of the signal transmitted to the communications device by modifying a beam pattern (beam pattern) and/or by modifying a pre-coding and/or by modifying a number of data streams of the signal transmitted using the multiplex method. Through the verification of the feedback signals, a more precise adjustment of the signal is therefore possible.
The feedback signal advantageously contains instructions for the modification of the signal transmitted to the communications device for the improvement of the transmission conditions. Especially within a closed-loop system of this kind, a high precision of the feedback signal is necessary. This is achieved by the measuring system and method according to the invention.
Accordingly, the testing of the feedback signal is guaranteed. The cost of the measuring system is low.
By preference, the measuring device is connected to the communications device. The measuring device preferably determines the actual reception quality by determining the bit-error rate and/or the data rate. A simple determination of the actual_ transmission quality is therefore achieved.
The antenna system is advarltageously a multiple antenna system. By preference, the communications device receives the signals by means of several antennae. In particular, in communications systems cf high complexity, it is possible to determine the accuracy of the feedback signals at low cost.
The measuring device preferably brings about the modification of the signal transmitted to the communications device by modifying a beam pattern (beam pattern) and/or by modifying a pre-coding and/or by modifying a number of data streams of the signal transmitted using the multiplex method. Through the verification of the feedback signals, a more precise adjustment of the signal is therefore possible.
The feedback signal advantageously contains instructions for the modification of the signal transmitted to the communications device for the improvement of the transmission conditions. Especially within a closed-loop system of this kind, a high precision of the feedback signal is necessary. This is achieved by the measuring system and method according to the invention.
4 By preference, the measuring device comprises a transmitter and a receiver. The transmitter and the receiver are preferably connected to the antenna system.
Accordingly, the use of further components is not necessary. Moreover, a simple calibration of the measuring system is achieved in this manner.
The measuring system preferably comprises a display device. The display device preferably presents intermediate results and/or results and/or parameters of the measurement. This guarantees an intuitive operation and logically-arranged display of the measurement results.
The communications system is preferably a MIMO
communications system. Especially in communications systems of high complexity, a low-cost for determining the accuracy of the feedback signals is possible.
The invention is described by way of example below with reference to the drawings, in which an advantageous exemplary embodiment of the invention is presented. The drawings are as follows:
Figure 1 shows an exemplary communications system;
Figure 2 shows a first exemplary communications link;
Figure 3 shows a second exemplary communications link;
Figure 4 shows a first exemplary embodiment of the measuring system according to the invention, and Figure 5 shows a second exemplary embodiment of the measuring system according to the invention.
The structure and function of a MIMO communications
Accordingly, the use of further components is not necessary. Moreover, a simple calibration of the measuring system is achieved in this manner.
The measuring system preferably comprises a display device. The display device preferably presents intermediate results and/or results and/or parameters of the measurement. This guarantees an intuitive operation and logically-arranged display of the measurement results.
The communications system is preferably a MIMO
communications system. Especially in communications systems of high complexity, a low-cost for determining the accuracy of the feedback signals is possible.
The invention is described by way of example below with reference to the drawings, in which an advantageous exemplary embodiment of the invention is presented. The drawings are as follows:
Figure 1 shows an exemplary communications system;
Figure 2 shows a first exemplary communications link;
Figure 3 shows a second exemplary communications link;
Figure 4 shows a first exemplary embodiment of the measuring system according to the invention, and Figure 5 shows a second exemplary embodiment of the measuring system according to the invention.
The structure and function of a MIMO communications
5 system will first be explained with reference to Figure 1. With reference to Figures 2- 5, the structure and function of various exemplary embodiments of the measuring system according to the invention will then be explained. The presentation and description of identical elements in similar drawings has not been repeated in some cases.
Figure 1 shows an exemplary communications system. The transmitter 10 is connected to several spatially-separate antennae 11. A receiver 14 is also connected to several spatially-separate antennae 13. The transmitter 10 transmits signals via the antennae 11. In this context, the signals are not necessarily identical. The signals are propagated over the propagation paths 12 and are received by the receivers 14 via the antennae 13. In this context, with N antennae 11 at the transmitter end and M
antennae 13 at the receiver end, there are N*M
propagation paths. By supplying the antennae 11 through the transmitters 10 with signals only slightly different in amplitude and phase, the totality of the antennae 11 can be impressed with a beam pattern corresponding to a single antenna. This factual situation will be explained in greater detail with refei ence to Figures 2 and Figure 3.
Figure 2 presents a first exemplary communications link.
An antenna system 20 is connected to a communications device 21. In this context, the antenna system 20 consists of a plurality of individual antennae arranged
Figure 1 shows an exemplary communications system. The transmitter 10 is connected to several spatially-separate antennae 11. A receiver 14 is also connected to several spatially-separate antennae 13. The transmitter 10 transmits signals via the antennae 11. In this context, the signals are not necessarily identical. The signals are propagated over the propagation paths 12 and are received by the receivers 14 via the antennae 13. In this context, with N antennae 11 at the transmitter end and M
antennae 13 at the receiver end, there are N*M
propagation paths. By supplying the antennae 11 through the transmitters 10 with signals only slightly different in amplitude and phase, the totality of the antennae 11 can be impressed with a beam pattern corresponding to a single antenna. This factual situation will be explained in greater detail with refei ence to Figures 2 and Figure 3.
Figure 2 presents a first exemplary communications link.
An antenna system 20 is connected to a communications device 21. In this context, the antenna system 20 consists of a plurality of individual antennae arranged
6 in a spatially-separate manner. These each provide their own beam pattern (beam pattern). The signals transmitted by the antennae differ from one another only slightly in amplitude and phase. Accordingly, a common beam pattern 22 is obtained for the overall antenna system 20. In this context, the schematically presented beam pattern 22 of the antenna system 20 is orientated in such a manner that the strongest propagation direction coincides with the communications device 21. The beam pattern can be modified by varying the amplitude and phase displacements of the antennae of the antenna system 20. This is illustrated with reference to Figure 3.
Figure 3 shows a second exemplary communications link. By comparison with the communications link shown in Figure 2, the amplitude and phase displacements of the antennae of the antenna system 20 have been modified. Accordingly, a different beam pattern 23 is obtained. The strongest propagation direction is now no longer disposed on the communications device 21 but above it. Accordingly, the transmission quality is poorer than in Figure 2. The communications device 21 determines the transmission conditions of the received signal and determines from this a feedback signal (feedback signal), which it communicates to the transmitter. In this context, the feedback signal contains instructions to the transmitter for the modification of the signal transmitted to the communications device 21 in order to achieve the best possible transmission conditions. In consequence, the transmitter adapts the signal, for example, corresponding to the beam pattern. The goal is to achieve an optimum reception quality of the communications device 21. A
displacement of the beam pattern as presented with
Figure 3 shows a second exemplary communications link. By comparison with the communications link shown in Figure 2, the amplitude and phase displacements of the antennae of the antenna system 20 have been modified. Accordingly, a different beam pattern 23 is obtained. The strongest propagation direction is now no longer disposed on the communications device 21 but above it. Accordingly, the transmission quality is poorer than in Figure 2. The communications device 21 determines the transmission conditions of the received signal and determines from this a feedback signal (feedback signal), which it communicates to the transmitter. In this context, the feedback signal contains instructions to the transmitter for the modification of the signal transmitted to the communications device 21 in order to achieve the best possible transmission conditions. In consequence, the transmitter adapts the signal, for example, corresponding to the beam pattern. The goal is to achieve an optimum reception quality of the communications device 21. A
displacement of the beam pattern as presented with
7 reference to Figure 2 and Figure 3 can also be achieved through a simple rotation of the antenna system 20.
However, in order to impleinent the adaptation of the signal illustrated here, for example, by tracking the beam pattern, the most accurate possible feedback signal is necessary. A measuring system for testing the accuracy of the feedback signal generated by a communications device is explained with reference to Figure 4 and Figure 5.
Figure 4 shows a first exenlplary embodiment of the measuring system according to the invention. An antenna system 30 consisting of several spatially separate antennae is connected to a measuring device 34.
Furthermore, the measuring device 34 is connected to a communications device 31.
The measuring device 34 transmits to the communications device 31 via the antenna system 30 with a beam pattern 32. The communications device 31 receives the signal and determines internally the transmission conditions. It transmits the feedback signal via the air interface and the antenna system 30 to the measuring device 34. In this context, the feedback signal is dependent on the measured transmission conditions. It contains instructions regarding how the transmitted signal is to be modified in order to improve the transmission conditions.
Alternatively, it can directly reflect the reception quality of the signal. This feedback signal is recorded by the measuring device 34. This can take place continuously or at given intervals. A cable-bound communication of the feedback signal is also conceivable.
For example, the communications device 31 in the
However, in order to impleinent the adaptation of the signal illustrated here, for example, by tracking the beam pattern, the most accurate possible feedback signal is necessary. A measuring system for testing the accuracy of the feedback signal generated by a communications device is explained with reference to Figure 4 and Figure 5.
Figure 4 shows a first exenlplary embodiment of the measuring system according to the invention. An antenna system 30 consisting of several spatially separate antennae is connected to a measuring device 34.
Furthermore, the measuring device 34 is connected to a communications device 31.
The measuring device 34 transmits to the communications device 31 via the antenna system 30 with a beam pattern 32. The communications device 31 receives the signal and determines internally the transmission conditions. It transmits the feedback signal via the air interface and the antenna system 30 to the measuring device 34. In this context, the feedback signal is dependent on the measured transmission conditions. It contains instructions regarding how the transmitted signal is to be modified in order to improve the transmission conditions.
Alternatively, it can directly reflect the reception quality of the signal. This feedback signal is recorded by the measuring device 34. This can take place continuously or at given intervals. A cable-bound communication of the feedback signal is also conceivable.
For example, the communications device 31 in the
8 exemplary embodiment does not transmits the feedback signal to the measuring device 34 via the air interface and the antenna system 30, but also communicates it via the direct connection.
At the same time, the measuring device 34 determines the actual reception quality via the direct link to the communications device 31. This is implemented, for example, by measuring the transmitted data volume or by determining the bit-error rate. The quality of the feedback signal can be estimated by comparison of the feedback signal and the ac-rual reception quality.
For a further increase in the accuracy of the measurement, the method described below can be used. The measuring device 34 adapts the signals, which are transmitted via the antenna system 30, until the communications device 31 transmits a feedback signal, which displays no further possibility for improvement of the transmission conditions. This can take place by a repetition of implemented signal-adaptation instructions as already explained, by an absence of further signal-adaptation instructions or a display of a maximum reception quality. At the same time, the measuring device 34 measures the actual reception quality, as described above. Following this, the ineasuring device 34 modifies the signals transmitted via the antenna system 30. Since, according to the feedback signal of the communications device 31, no further improvement of the transmission conditions can be achieved, it is anticipated that the actually measured reception quality will be impaired by any change to the signals. T.f this is not the case, the feedback signal will deviate from the real reception
At the same time, the measuring device 34 determines the actual reception quality via the direct link to the communications device 31. This is implemented, for example, by measuring the transmitted data volume or by determining the bit-error rate. The quality of the feedback signal can be estimated by comparison of the feedback signal and the ac-rual reception quality.
For a further increase in the accuracy of the measurement, the method described below can be used. The measuring device 34 adapts the signals, which are transmitted via the antenna system 30, until the communications device 31 transmits a feedback signal, which displays no further possibility for improvement of the transmission conditions. This can take place by a repetition of implemented signal-adaptation instructions as already explained, by an absence of further signal-adaptation instructions or a display of a maximum reception quality. At the same time, the measuring device 34 measures the actual reception quality, as described above. Following this, the ineasuring device 34 modifies the signals transmitted via the antenna system 30. Since, according to the feedback signal of the communications device 31, no further improvement of the transmission conditions can be achieved, it is anticipated that the actually measured reception quality will be impaired by any change to the signals. T.f this is not the case, the feedback signal will deviate from the real reception
9 quality. An optimal adaptation of the transmitted signals is not possible with this sub-optimal feedback.
Figure 5 shows a second exemplary embodiment of the measuring system according to the invention. Here, the structure of the measuring system is presented in greater detail. A processing device 42 is connected to a display device 44, the transmitter 40, a receiver 41 and an interface 43. The transmitter 40 and the receiver 41 are connected to the antenna system 30. The interface 43 is connected to the communications device 31.
The processing device 42 generates signals, which are transmitted to the communications device 31 via the transmitter 40, the antenna system 30 and the air interface. The communications device 31 transmits via the air interface, the antenna system 30 and the receiver 41 signals, which are processed by the processing device 42.
These signals contain feedback signals, which are generated dependent upon the transmission conditions determined by the communications device 31. The receiver can be dispensed with, if t;.Ile feedback signals are also transmitted to the processing device 42 via the interface 43. The processing device 42 modifies the signals transmitted via the transmitter 40 and therefore changes the signals, here, for example, the beam pattern 32 of the signal transmitted by the antenna system 30.
The processing device 42 is connected to the communications device 31 via the interface 43. By means of this link, the processing device 42 determines the actual transmission quality, for example, on the basis of the transmission rate or the bit-error rate achieved by the communications device 31. The processing device 42 compares the feedback sigrials with the transmission quality measured via the interface 43. Accordingly, it is possible to evaluate the quality of the feedback signals generated by the communications device.
The invention is not restricted to the exemplary embodiment presented. As already mentioned, different communications systems can be used. For example, MIMO
systems and also systems with only one antenna at the
Figure 5 shows a second exemplary embodiment of the measuring system according to the invention. Here, the structure of the measuring system is presented in greater detail. A processing device 42 is connected to a display device 44, the transmitter 40, a receiver 41 and an interface 43. The transmitter 40 and the receiver 41 are connected to the antenna system 30. The interface 43 is connected to the communications device 31.
The processing device 42 generates signals, which are transmitted to the communications device 31 via the transmitter 40, the antenna system 30 and the air interface. The communications device 31 transmits via the air interface, the antenna system 30 and the receiver 41 signals, which are processed by the processing device 42.
These signals contain feedback signals, which are generated dependent upon the transmission conditions determined by the communications device 31. The receiver can be dispensed with, if t;.Ile feedback signals are also transmitted to the processing device 42 via the interface 43. The processing device 42 modifies the signals transmitted via the transmitter 40 and therefore changes the signals, here, for example, the beam pattern 32 of the signal transmitted by the antenna system 30.
The processing device 42 is connected to the communications device 31 via the interface 43. By means of this link, the processing device 42 determines the actual transmission quality, for example, on the basis of the transmission rate or the bit-error rate achieved by the communications device 31. The processing device 42 compares the feedback sigrials with the transmission quality measured via the interface 43. Accordingly, it is possible to evaluate the quality of the feedback signals generated by the communications device.
The invention is not restricted to the exemplary embodiment presented. As already mentioned, different communications systems can be used. For example, MIMO
systems and also systems with only one antenna at the
10 transmitter and/or receiver end can be used. An integration of the measuring device and of the antenna system into one device is also conceivable. All of the features described above or illustrated in the drawings can be advantageously combined with one another as required within the framework of the invention.
Claims (14)
1. A method for testing a feedback signal transmitted by a communications device (21, 31) within a communications system, wherein the communications device (21, 31) generates the feedback signal dependent upon transmission conditions of a signal received via the air interface, which it has determined, wherein the actual reception quality of the signal in the communications device (21, 31) is additionally measured, wherein the following stages are implemented:
- modification of the signals transmitted to the communications device (21, 31) in such a manner that the transmitted feedback signal displays no further possibility for improving the transmission conditions;
- modification of the position of the communications device (21, 31) and/or of the source of the signal transmitted to the communications device (21, 31) and/or modification of the transmitted signal; and - determination of a quality of the feedback signal by comparison of the feedback signal and the actual reception quality.
- modification of the signals transmitted to the communications device (21, 31) in such a manner that the transmitted feedback signal displays no further possibility for improving the transmission conditions;
- modification of the position of the communications device (21, 31) and/or of the source of the signal transmitted to the communications device (21, 31) and/or modification of the transmitted signal; and - determination of a quality of the feedback signal by comparison of the feedback signal and the actual reception quality.
2. The method according to claim 1, characterised in that the actual reception quality is determined by determining the bit-error rate and/or the data rate.
3. The method according to claim 1 or 2, characterised in that the signal is transmitted to the communications device (21, 31) by means of several antennae (20, 30), and that the communications device (21, 31) receives the signals by means of several antennae.
4. The method according to any one of claims 1 to 3, characterised in that the modification of the signal transmitted to the communications device (21, 31) is implemented by modifying a beam pattern (beam pattern) (22, 23, 32) and/or by modifying a pre-coding and/or by modifying a number of data streams of the signal transmitted using the multiplex method.
5. The method according to any one of claims 1 to 4, characterised in that.
the feedback signal contains instructions for the modification of the signal transmitted to the communications device (21, 31) for the improvement of the transmission conditions.
the feedback signal contains instructions for the modification of the signal transmitted to the communications device (21, 31) for the improvement of the transmission conditions.
6. The method according to any one of claims 1 to 5, characterised in that the communications system is a MIMO communications system.
7. A measuring system for testing a feedback signal transmitted by a communications device (21, 31) within a communications system with an antenna system (20, 30) and a measuring device (34), wherein the measuring device (34) transmits a signal via an air interface and the antenna system (20, 30) to a communications device (21, 31), wherein the communications device (21, 31) receives the signal and generates a feedback signal dependent upon transmission conditions of the signal, which it has determined, and transmits it to the measuring device (34), wherein the measuring device (34) measures an actual reception quality of the signal in the communications device (21, 31), wherein the measuring system implements the following stages:
- modification of the signals transmitted to the communications device (21, 31) in such a manner that the transmitted feedback signal displays no further possibility of improvement of the transmission conditions;
- modification of the position of the communications device (21, 31) and/or of the antenna system (20, 30) and/or modification of the transmitted signal, and - determination of a quality of the feedback signal by comparison of the feedback signal and the actual reception quality.
- modification of the signals transmitted to the communications device (21, 31) in such a manner that the transmitted feedback signal displays no further possibility of improvement of the transmission conditions;
- modification of the position of the communications device (21, 31) and/or of the antenna system (20, 30) and/or modification of the transmitted signal, and - determination of a quality of the feedback signal by comparison of the feedback signal and the actual reception quality.
8. The measuring system according to claim 7, characterised in that the measuring device (34) is connected to the communications device (21, 31), and that the measuring device (34) determines the actual reception quality by determining the bit-error rate and/or the data rate.
9. The measuring system according to claim 7 or 8, characterised in that the antenna system (20, 30) is a multiple antenna system, and that the communications device (21, 31) receives the signals by means of several antennae.
10. Measuring system according to any one of claims 7 to 9, characterised in that the measuring device (34) brings about the modification of the signal transmitted to the communications device (21, 31) by modifying a beam pattern (beam pattern.) (22, 23, 32) and/or by modifying a pre-coding and/or by modifying a number of data streams of the signal transmitted using the multiplex method.
11. The measuring system according to any one of claims 7 to 10, characterised in that the feedback signal contains instructions for the modification of the signal transmitted to the communications device (21, 31) for the improvement of the transmission conditions.
12. The measuring system according to any one of claims 7 to 11, characterised in that the measuring system (34) comprises a transmitter (40) and a receiver (41), and that the transmitter (40) and the receiver (41) are connected to the antenna system (20, 30).
13. The measuring system according to any one of claims 7 to 12, characterised in that:
the measuring device (34) comprises a display device (44) and that the display device (44) presents intermediate results and/or results and/or parameters of the measurement.
the measuring device (34) comprises a display device (44) and that the display device (44) presents intermediate results and/or results and/or parameters of the measurement.
14. The measuring system according to any one of claims 7 to 13, characterised in that the communications system is a MIMO communications system.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102008020141A DE102008020141A1 (en) | 2008-04-22 | 2008-04-22 | Assessment of feedback quality in communication systems |
| DE102008020141.3 | 2008-04-22 | ||
| PCT/EP2009/002436 WO2009129917A1 (en) | 2008-04-22 | 2009-04-02 | Evaluation of the feedback quality in communication systems |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2694319A1 true CA2694319A1 (en) | 2009-10-29 |
| CA2694319C CA2694319C (en) | 2016-05-24 |
Family
ID=40810169
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2694319A Active CA2694319C (en) | 2008-04-22 | 2009-04-02 | Evaluation of the feedback quality in communications systems |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US8340164B2 (en) |
| EP (1) | EP2291933B1 (en) |
| JP (1) | JP5269185B2 (en) |
| KR (1) | KR101525905B1 (en) |
| CN (1) | CN101689939B (en) |
| AT (1) | ATE523976T1 (en) |
| CA (1) | CA2694319C (en) |
| DE (1) | DE102008020141A1 (en) |
| WO (1) | WO2009129917A1 (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102009023989A1 (en) * | 2009-06-05 | 2010-12-16 | Rohde & Schwarz Gmbh & Co. Kg | Measuring method for determining bit error rate and/or data transfer rate of communication link between communication subscribers, involves comparing measurement package with another measurement package from communication subscriber |
| DE102010046095A1 (en) * | 2010-09-21 | 2012-03-22 | Rohde & Schwarz Gmbh & Co. Kg | Measuring unit and method for transmission parameter measurement of a DUT |
| CN102468893B (en) * | 2010-11-17 | 2016-04-13 | 中兴通讯股份有限公司 | The method and system of test performance of multi-input multi-output |
| KR102105567B1 (en) * | 2014-01-09 | 2020-04-28 | 한국전자통신연구원 | Apparatus and method for processing mmt signaling message |
| US9660739B2 (en) * | 2015-02-09 | 2017-05-23 | Spirent Communications, Inc. | System and methods of testing adaptive antennas |
| US10243628B2 (en) | 2015-07-16 | 2019-03-26 | Spirent Communications, Inc. | Massive MIMO array emulation |
| CN106375949B (en) * | 2015-07-21 | 2019-12-03 | 丰唐物联技术（深圳）有限公司 | A kind of terminal node wireless signal measurement method and device |
| US10244411B2 (en) | 2016-06-14 | 2019-03-26 | Spirent Communications, Inc. | Over the air testing for massive MIMO arrays |
| IT201600072521A1 (en) * | 2016-07-12 | 2018-01-12 | Inst Rundfunktechnik Gmbh | MOBILFUNKKOMMUNIKATION MIT VERBESSERTER SENDE- UND EMPFANGSQUALITÄT |
| US10136341B2 (en) * | 2017-01-03 | 2018-11-20 | Simmonds Precision Products, Inc. | Wireless data concentrator systems and methods |
| US10587350B2 (en) | 2017-10-12 | 2020-03-10 | Spirent Communications, Inc. | Calibrating a programmable phase matrix and channel emulator and performing massive MIMO array testing using the calibrated phase matrix and channel emulator |
| US10313034B2 (en) | 2017-10-12 | 2019-06-04 | Spirent Communications, Inc. | Massive MIMO array testing using a programmable phase matrix and channel emulator |
| US11515903B2 (en) | 2020-08-25 | 2022-11-29 | Antennas Direct, Inc. | Signal level indicators and antenna assemblies including the same |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5982760A (en) * | 1997-06-20 | 1999-11-09 | Qualcomm Inc. | Method and apparatus for power adaptation control in closed-loop communications |
| US6850736B2 (en) * | 2000-12-21 | 2005-02-01 | Tropian, Inc. | Method and apparatus for reception quality indication in wireless communication |
| US7499709B2 (en) * | 2002-02-07 | 2009-03-03 | Alcatel-Lucent Usa Inc. | Method and apparatus for closed loop transmit diversity in a wireless communications system |
| US8121536B2 (en) * | 2002-07-23 | 2012-02-21 | Qualcomm Incorporated | Noise compensation in satellite communications |
| US20050170782A1 (en) * | 2004-02-04 | 2005-08-04 | Nokia Corporation | Method and apparatus to compensate quantization error of channel quality report |
| WO2006107037A1 (en) * | 2005-04-04 | 2006-10-12 | Nec Corporation | Ofdm communication system, method for generating feedback information thereof, and communication apparatus |
| US7715318B2 (en) * | 2005-08-25 | 2010-05-11 | Interdigital Technology Corporation | Communication apparatus and method using forward error correcting statistics for adaptive modulation feedback |
| CN100550685C (en) * | 2005-10-05 | 2009-10-14 | 中兴通讯股份有限公司 | The method and system of down link self adaption in the multiuser mimo system |
| US8760994B2 (en) * | 2005-10-28 | 2014-06-24 | Qualcomm Incorporated | Unitary precoding based on randomized FFT matrices |
| EP1987696A4 (en) * | 2006-02-08 | 2014-04-09 | Lg Electronics Inc | Method of transmitting channel quality information in mobile communication system |
| AU2007282272B2 (en) * | 2006-08-09 | 2010-09-23 | Lg Electronics Inc. | Method of estimating signal-to-noise ratio, method of adjusting feedback information transmission, adaptive modulation and coding method using the same, and transceiver thereof |
| KR101249359B1 (en) | 2006-08-18 | 2013-04-01 | 삼성전자주식회사 | Method and apparatus for transmitting/receiving channel quality information in an orthogonal frequency division multiplexing system supporting a multi-input multi-output |
| TW200901655A (en) * | 2007-03-21 | 2009-01-01 | Interdigital Tech Corp | Method and apparatus for communicating precoding or beamforming information to users in MIMO wireless communication systems |
-
2008
- 2008-04-22 DE DE102008020141A patent/DE102008020141A1/en not_active Withdrawn
-
2009
- 2009-04-02 AT AT09735953T patent/ATE523976T1/en active
- 2009-04-02 CA CA2694319A patent/CA2694319C/en active Active
- 2009-04-02 EP EP09735953A patent/EP2291933B1/en active Active
- 2009-04-02 JP JP2011505394A patent/JP5269185B2/en active Active
- 2009-04-02 US US12/602,746 patent/US8340164B2/en active Active
- 2009-04-02 KR KR1020097026852A patent/KR101525905B1/en active IP Right Grant
- 2009-04-02 CN CN2009800005089A patent/CN101689939B/en active Active
- 2009-04-02 WO PCT/EP2009/002436 patent/WO2009129917A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| CN101689939A (en) | 2010-03-31 |
| CA2694319C (en) | 2016-05-24 |
| CN101689939B (en) | 2012-12-05 |
| US20100177813A1 (en) | 2010-07-15 |
| KR101525905B1 (en) | 2015-06-04 |
| EP2291933B1 (en) | 2011-09-07 |
| JP2011519532A (en) | 2011-07-07 |
| EP2291933A1 (en) | 2011-03-09 |
| JP5269185B2 (en) | 2013-08-21 |
| US8340164B2 (en) | 2012-12-25 |
| DE102008020141A1 (en) | 2009-10-29 |
| KR20100135164A (en) | 2010-12-24 |
| ATE523976T1 (en) | 2011-09-15 |
| WO2009129917A1 (en) | 2009-10-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2694319C (en) | Evaluation of the feedback quality in communications systems | |
| EP3890199B1 (en) | Method and system for testing wireless performance of wireless terminal | |
| US20160344490A1 (en) | System and method for calibration and monitoring of an anechoic boundary array rf environment simulator | |
| CN102257743B (en) | A system for wireless communication and a method for providing wireless communication | |
| US20100171650A1 (en) | Multi-antenna measurement method and multi-antenna measurement system | |
| CN103138817B (en) | A kind of for selecting the method and apparatus of ul transmissions antenna | |
| JP4976504B2 (en) | Method and apparatus for improving transmission efficiency in a mobile radio communication system | |
| US20150071335A1 (en) | Systems and methods for compensating antenna gain imbalance | |
| US20100248641A1 (en) | Test equipment and mobile radio device and a method for testing a mobile radio device | |
| US20100321233A1 (en) | Method for calibrating antenna arrays | |
| CA2561549A1 (en) | Calibration of transmit and receive chains in a mimo communication system | |
| WO2008023315A3 (en) | Transform-domain feedback signaling for mimo communication | |
| CA2869097C (en) | System and method for power control in mimo systems | |
| US20150288462A1 (en) | Method for Channel Calibration | |
| US8009096B2 (en) | Method, system and apparatus for determining antenna weighting for transmit diversity | |
| CN103139817B (en) | The method and device of diagnosing base station channel failure | |
| US10356826B2 (en) | Simultaneous bidirectional wireless link | |
| US20120302159A1 (en) | Measuring instrument and a measuring method for stationary testing of mobile-radio relay stations | |
| JP2013506331A (en) | Device and method for measuring channel quality feedback from a mobile station | |
| KR101706204B1 (en) | Method of correcting transceiver of radio channel measurement system with multiple antennas | |
| KR20130086870A (en) | Method for transmitting signal of multiple antennas base station and apparatus thereof | |
| CN101120533A (en) | Method for determining an optimal data transfer rate via a transfer medium | |
| SE512656C2 (en) | Procedure for reducing fading in a telecommunications system | |
| KR20030069664A (en) | Apparatus and method for verifying a base station in mobile communication system | |
| KR20090101916A (en) | Method and apparatus for improving transmission efficiency in a mobile radio communications system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request |
Effective date: 20140117 |